Low intensity lighting installations provide enhanced safety and decorative properties to a vehicle body or driver helmet. Low intensity vehicle body lighting was largely impractical with incandescent bulbs owing to problems associated with high vertical profiles and heat management. More recently, other approaches to backlighting vehicle body features have invoked direct lighting with a light emitting diode. U.S. Pat. No. 6,244,734 is representative of such efforts. However, such efforts have met with limited acceptance owing to intensity variation along the length of a feature such as a vehicle door kick plate. Intensity variations have been in part compensated for by a linear array of light emitting diodes or the use of a distant light emitting diode having light emission transmitted from beneath a lighted feature with a light pipe. U.S. Pat. No. 6,036,340 and U.S. Patent Application Publication 2002/0017267 A1 are representative of such efforts.
A remote light emitting diode has previously been coupled to the terminus of a fiber optic bundle to provide lit piping within a vehicle interior. U.S. Pat. No. 6,854,869 is representative of such systems. Unfortunately, the fiber optic bundle outer layers obscure emission from fiber optics within the interior of the bundle and as a result provide insufficient intensity to backlight a transparent or translucent overlay positioned parallel to the fiber optic bundle.
Still other attempts to provide vehicle exterior low intensity backlighting have included resort to electroluminescent sheeting deployed directly beneath the feature. Electroluminescent backlighting in a vehicle context has been limited to a narrow range of applications perceived to be of high value owing to the stringent electrical input requirements, material costs and susceptibility to environmental degradation. U.S. Pat. No. 5,641,221 is representative of vehicle electroluminescent backlighting.
Thus, there exists a need for a vehicle exterior backlighting system that achieves a high degree of illumination uniformity across a feature so as to overcome the limitations of the prior art.